Arowanas are massive freshwater fish which have bony heads and elongated bodies. There are ten distinct types of arowanas: four can be identified in Southeast Asia, 3 in South America, two in Australia, and 1 from Africa. Recognized as the â€œKing of Tropical Fishâ€, these fish are large â€“ the South American arapaima (also identified as pirarucu) can increase up to 8.2 toes (2.5 meters) in size, Creating it 1 of the biggest freshwater fish on the world â€“ and are able of carrying out extraordinary feats that handful of other fish can match.